Device for covering the steam exhaust pipe of locomotives



March 2, 1937. M, LEMAlTRE 2,072,599

DEVICE FOR COVERING THE STEAM EXHAUST PIPE GF LOCOMOTIVES Filed Feb. 1'7, 1936 Patented Mar. 2, 1937 PATENT OFFICE 2,072,599 j DEvIoE Fon covERING THE nSTEAM EXHAUST PIPE F f LOCOMOTIVES Maurice Lematre, Marcinelle, Belgium Application February 17, 1936, Serial No. 64,419 In France February 26, 1935 1 Claim.

The present invention relates to a device for covering the outlet of the steam exhaust pipe of locomotives and comprising a rim of nozzles forming a long neck and separated one from the other to an extent such that the smoke can easily obtain access to the interior of the said rim or ring by passing between the nozzles.

Devices of this nature are known in which the said nozzles have vertical axes and owing to this they direct the jets of steam which leave them approximately parallel to the wall of the smoke stack at a certain distance from this wall. In these devices, a part of thesmoke remains in con tact with the surface of the smoke stack and is checked by this surface, whilst the steam escapes freely.

The present invention has for its object a device ensuring a more efficient entrainment of the smoke by the exhaust steam.

To this end, the said nozzles separate upwards in such manner that the jets of steam emerging therefrom are directed against the walls of the smoke stack.

Owing to this arrangement of the nozzles, the steam is distributed in the zone of the stack close to the walls thereof which completely prevents the smoke from emerging from the stack by moving along the said wall. This device effects a certain slackening of the steam by the wall and prevents the slackening of the smoke. It thus tends to equalize the speeds of exhaust of the steam and of the smoke into the atmosphere. Furthermore, it effects an individual flattening of each jet of steam on the wall of the stack. This attening of each jet gives rise to eddies owing to which the smoke which has easy access to the centre of the stack by passing between the well separated nozzles and the lower portion of the steam jets, is eiectively mixed with the steam and carried along thereby.

The device according to the invention thus gives rise to effects entirely different to those caused by the devices which, with the object of distributing the steam over .all the cross-section of the stack, are constituted by one piece which covers the exhaust pipe and which is bored with a large number of inclined holes so as to separate upwards. These known devices form at the outlet of the said part, steam screens through which the smoke can only pass with great diiculty towards the centre of the stack and almost the whole of the smoke is obliged to pass into the annular space between the mass of steam and the wall of the stack without being able to mix with 55 the steam.

(Cl. 23o- 100) The annexed drawing represents diagrammatically and only by way of example, one form of device according to the invention.

Figure 1 is a vertical diametrical section of this device on the line I-I of Figure 2.

Figure 2 is a plan view of the device according to Figure 1, on which is represented by square rulings the section oi the stack approximately occupied by the steam.

Figure 3 is a section on the line III-III of Figure 1 on which is shown by square rulings the section occupied by the steam at the position of the section.

In these different gures, the like reference numerals indicate the like parts.

In Figure l there is shown in a smoke box 2 of a locomotive a steam exhaust pipe 3 which carries at its upper end a device for directing steam jets onto the walls of the smoke stack 5. This device comprises a number of nozzles 4 (Figures 1 .and 2) arranged in a ring at considerable distance one from the other in order that the smoke can easily pass between them to the interior of the said ring. The nozzles 4 are outwardly inclined so as to diverge in an upward direction. This inclination is such that the jets of steam emerging therefrom meet the walls of the smoke stack 5 at a short distance above the' nozzles. Two of these steam jets are shown in Figure 1 and are indicated by 6.

The jets of steam which emerge from the nozzles 4 remain for a certain length quite distant one from the other owing to the considerable distance which separates the nozzles from which they emerge. The smoke can thus easily pass towards the centre of the smoke stack 5 between these jets.

At the level of the section of Figure 3, the jets of steam meet the walls of the smoke stack. Their section is represented by the cross line surface of this gure. They still permit an easy passage of the smoke between them. Higher up the stack 5 these jets Hatten against the walls and prevent the smoke from coming into contact therewith. At the outlet of the stack, the steam occupies for example the section represented by the square ruled surface of Figure 2. The smoke which is in the centre of the stack mixes with the steam owing to the eddies produced by the flattening.

It is evident that the invention is not restricted to the embodiment which has been described and that many modifications may be made in the form and constitution of the parts employed in its construction without departing from the scope of the invention. Thus, the manner in which the nozzles 4 are disposed can naturally Vary as a function of the form of the cross-section of the smoke stack, in order to be approximately parallel to the periphery of this section.

Moreover, in addition to the said nozzles 4, the device according to the invention may comprise a vertical central nozzle such as 'I which if necessary can be more or less obstructed.

What I claim is:

In a locomotive, a steam exhaust pipe disposed in the smoke box, a smoke stack over said pipe and a device on said pipe comprising a ring of nozzles with a long neck separated one from the other to an extent such that the smoke can easily obtain direct access to the interior of said ring by passing between said nozzles, the latter having their axes inclined relative to the interior wall of the smoke stack in such a manner that the jets of steam emerging therefrom are directed against the inferior part of said Wall and leave a free space for the smoke at the interior of the ring of steam they form along the interior wall of the l0 smoke stack.

MAURICE LEMATRE. 

